open_stack_interface.py: VM booting no longer happens in a separate thread.  Since we don't do the boot followed by re-boot, the boot is fairly fast.  Also, creation of a separate thread was resulting in complications such is figuring out when exactly the VM is at a point where mac addresses are available, etc.
open_stack_interface.py: VM booting no longer happens in a separate thread.  Since we don't do the boot followed by re-boot, the boot is fairly fast.  Also, creation of a separate thread was resulting in complications such is figuring out when exactly the VM is at a point where mac addresses are available, etc.

GENI-NSF/gram,GENI-NSF/gram,GENI-NSF/gram